Electronic devices, such as cellular telephones, cameras, and computers, commonly use a lens module in conjunction with an image sensor to capture images. Many imaging systems employ autofocus methods and various signal processing techniques to improve image quality by adjusting the position of the lens relative to the image sensor.
Autofocus systems generally utilize a driver and an actuator to move the lens to an optimal position to increase the image quality. The system also utilizes operation amplifiers to facilitate signal propagation. The operation amplifier, however, may experience an offset voltage, which results in the driver producing an output current that differs from an expected (ideal) current. For high performance drivers, the variation between the actual output current and the ideal must be reduced or removed.